1. Field of the Invention
The invention relates generally to safety devices, and relates specifically to a structure adapted for use in a door of a refrigerated compartment, for preventing physical contact with a portion of an electrical circuit which could otherwise be exposed.
2. Description of the Prior Art
Refrigerated compartments are utilized for the display and sale of a wide variety of products, such as food products including dairy and meat, and beverages such as wine. Such refrigerated compartments often include doors for access thereinto, and each door may include two or more glass panes therein. The panes are spaced apart by spacers which extend about the top, bottom and sides thereof so as to form at least one insulating air space therebetween. The panes are bonded together at the edges thereof, and a frame holds the panes in the door.
By virtue of the temperature differential between the temperature outside and inside the refrigerated compartment, the portions of the panes of glass exposed to the relatively high humidity store ambient conditions are subject to the formation of condensation thereon. To prevent the formation of such condensation, the inside surface of one or more of the panes of glass, typically the outer pane, is coated with a transparent conductive coating to which an electrical power supply circuit extends. The circuit is connected on the inner surface of such coated pane, so as to conduct electric current to the conductive coating for heating thereof, to prevent the formation of condensation. The electrical circuit typically includes a bus bar positioned on the inside surface of the coated pane of glass, a conductive lead to the bus bar, and contact means at the point of connection of the conductive lead and bus bar. The bus bar is covered on the outside of the coated pane by the frame holding the glass in the door.
Tempered glass panes have been utilized in such refrigerated compartment doors for safety, as such panes shatter into small pieces upon breakage thereof rather than forming dangerous large pieces of glass. The shattering of the coated pane of glass breaks the continuity of the electrical circuit through the bus bar mounted on the inner surface thereof, which prevents shock from contact therewith. However, a portion of the electrical circuit proximate the contact means normally remains conductive and could be exposed on the inside surface of the pane of glass through the air space. Such otherwise exposed circuit portion may include a portion of the conductive lead, a portion of the bus bar, and the contact means, posing a potential threat to persons coming into physical contact therewith.